Abstract：The operating mode of the flywheel energy storage system (FESS) requires the flywheel to be charged reliably in the shortest time. The traditional charging control strategy adopts vector control with the speed loop or voltage loop as the outer loop, which has low charging efficiency and poor dynamic performance. Moreover, it is separate from the operating mode of FESS, which cannot realize the energy control and speed stability of the flywheel motor at the same time. The traditional implementation of the operating mode of FESS needs to be more flexible, and the electromagnetic torque will jump, which affects the system’s stability. Besides, the power loss and load power of the flywheel motor can cause the charging power to drop and affect the system’s robustness. Therefore, this paper proposes an optimized charging control strategy (OCCS) based on a nonlinear disturbance observer (NDOB). Firstly, the outer loop adopts the combination of speed control and energy control, the speed loop realizes constant torque control, and the energy loop uses flywheel kinetic energy as a control variable to realize constant power control. Secondly, the transition control unit is proposed to realize the smooth switching between constant torque control and constant power control. Thirdly, the NDOB estimates motor power loss and load power to perform feedforward compensation. Moreover, the transfer function of the energy-current double closed-loop system considering NDOB is derived. Finally, based on the steady-state, dynamic, and anti-disturbance performance requirements of the control system, a controller parameter design method is given. The experimental results show that in the charging process, the maximum peak-to-peak value of phase currents of OCCS is 480 A. The sudden change of the phase currents is avoided, but the charging time is still sacrificed. OCCS+NDOB applies the NDOB to estimate motor power loss and load power, reducing the charging time. The proposed charging control strategy has no torque jump in the switching process from constant torque control to constant power control, and the switching process is smooth. The maximum torque of OCCS+NDOB is 188.5 N·m, which is 18.5 % lower than 231.3 N·m of the improved charge control strategy 1 (ICCS1). In addition, compared with the improved charge control strategy 2 (ICCS2) and OCCS, OCCS+NDOB has significantly shorter charging time and higher charging efficiency. The charging time of OCCS+NDOB from 4 000 r/min to 10 000 r/min is about 21.13 s, which is consistent with ICCS1, while the charging times of ICCS2 and OCCS are 26.01 s and 24.36 s, respectively. Compared with OCCS, the charging time of OCCS+NDOB is reduced by 13.3 %. Therefore, although introducing a transition control unit increases the charging time, the charging efficiency can be improved by NDOB. In the constant power control unit, the actual power of OCCS+NDOB can reach 100 kW, while other strategies cannot reach 100 kW due to the motor power loss and load power. The total power loss observed by NDOB in the experiment is 2.15 kW. The conclusions can be drawn as follows: (1) the feasibility of combining speed control and energy control in the outer loop of FESS is verified. The speed loop realizes constant torque control, and the energy loop realizes constant power control. (2) The transition control unit is introduced to realize the smooth switching from constant torque control to constant power control, and the jump of electromagnetic torque is avoided. (3) The NDOB is used to estimate the motor power loss and load power, and the feedforward compensation control is carried out, which improves the anti-disturbance ability and dynamic performance of the system, further reducing the charging time.
李忠瑞, 聂子玲, 艾胜, 许杰, 曹美禾. 一种基于非线性扰动观测器的飞轮储能系统优化充电控制策略[J]. 电工技术学报, 2023, 38(6): 1506-1518.
Li Zhongrui, Nie Ziling, Ai Sheng, Xu Jie, Cao Meihe. An Optimized Charging Control Strategy for Flywheel Energy Storage System Based on Nonlinear Disturbance Observer. Transactions of China Electrotechnical Society, 2023, 38(6): 1506-1518.
[1] Mousavi G S M, Faraji F, Majazi A, et al. A com- prehensive review of flywheel energy storage system technology[J]. Renewable and Sustainable Energy Reviews, 2017, 67: 477-490. [2] 张维煜, 朱熀秋. 飞轮储能关键技术及其发展现状[J]. 电工技术学报, 2011, 26(7): 141-146. Zhang Weiyu, Zhu Huangqiu.Key technologies and development status of flywheel energy storage system[J]. Transactions of China Electrotechnical Society, 2011, 26(7): 141-146. [3] Tziovani L, Hadjidemetriou L, Charalampous C, et al.Energy management and control of a flywheel storage system for peak shaving applications[J]. IEEE Transa- ctions on Smart Grid, 2021, 12(5): 4195-4207. [4] 纪锋, 付立军, 王公宝, 等. 舰船综合电力系统飞轮储能控制器设计[J]. 中国电机工程学报, 2015, 35(12): 2952-2959. Ji Feng, Fu Lijun, Wang Gongbao, et al.Controller design of flywheel energy storage for vessel integrated power systems[J]. Proceedings of the CSEE, 2015, 35(12): 2952-2959. [5] 隋云任, 梁双印, 黄登超, 等. 飞轮储能辅助燃煤机组调频动态过程仿真研究[J]. 中国电机工程学报, 2020, 40(8): 2597-2606. Sui Yunren, Liang Shuangyin, Huang Dengchao, et al.Simulation study on frequency modulation process of coal burning plants with auxiliary of flywheel energy storage[J]. Proceedings of the CSEE, 2020, 40(8): 2597-2606. [6] 李树胜, 付永领, 刘平, 等. 磁悬浮飞轮储能UPS系统集成应用及充放电控制方法研究[J]. 中国电机工程学报, 2017, 37(增刊1): 170-176. Li Shusheng, Fu Yongling, Liu Ping, et al.Research on integrated application and charging-discharging control method for the magnetically suspended flywheel storage-based UPS system[J]. Proceedings of the CSEE, 2017, 37(S1): 170-176. [7] 李进, 张钢, 刘志刚, 等. 城轨交通用飞轮储能阵列控制策略[J]. 电工技术学报, 2021, 36(23): 4885-4895. Li Jin, Zhang Gang, Liu Zhigang, et al.Control strategy of flywheel energy storage array for urban rail transit[J]. Transactions of China Electrotechnical Society, 2021, 36(23): 4885-4895. [8] 陈云龙, 杨家强, 张翔. 一种计及总损耗功率估计与转速前馈补偿的飞轮储能系统放电控制策略[J]. 中国电机工程学报, 2020, 40(7): 2358-2368, 2414. Chen Yunlong, Yang Jiaqiang, Zhang Xiang.A discharge strategy for flywheel energy storage systems based on feedforward compensation of observed total dissipative power and rotational speed[J]. Proceedings of the CSEE, 2020, 40(7): 2358-2368, 2414. [9] Zhang Xiang, Yang Jiaqiang.A robust flywheel energy storage system discharge strategy for wide speed range operation[J]. IEEE Transactions on Industrial Electronics, 2017, 64(10): 7862-7873. [10] 王安邦, 姜卫东, 王群京, 等. 转子动能为外环控制量的永磁同步电动机双闭环矢量控制策略[J]. 电工技术学报, 2015, 30(18): 112-120. Wang Anbang, Jiang Weidong, Wang Qunjing, et al.Dual closed loop vector control strategy for PMSM using rotor kinetic energy as the outer loop controlling parameter[J]. Transactions of China Electrotechnical Society, 2015, 30(18): 112-120. [11] 刘文军, 周龙, 唐西胜, 等. 基于改进型滑模观测器的飞轮储能系统控制方法[J]. 中国电机工程学报, 2014, 34(1): 71-78. Liu Wenjun, Zhou Long, Tang Xisheng, et al.Research on FESS control based on the improved sliding-mode observer[J]. Proceedings of the CSEE, 2014, 34(1): 71-78. [12] 李群湛, 王喜军, 黄小红, 等. 电气化铁路飞轮储能技术研究[J]. 中国电机工程学报, 2019, 39(7): 2025-2033. Li Qunzhan, Wang Xijun, Huang Xiaohong, et al.Research on flywheel energy storage technology for electrified railway[J]. Proceedings of the CSEE, 2019, 39(7): 2025-2033. [13] 戴兴建, 姜新建, 王秋楠, 等. 1MW/60MJ飞轮储能系统设计与实验研究[J]. 电工技术学报, 2017, 32(21): 169-175. Dai Xingjian, Jiang Xinjian, Wang Qiunan, et al.The design and testing of a 1MW/60MJ flywheel energy storage power system[J]. Transactions of China Electrotechnical Society, 2017, 32(21): 169-175. [14] 刘学, 姜新建, 张超平, 等. 大容量飞轮储能系统优化控制策略[J]. 电工技术学报, 2014, 29(3): 75-82. Liu Xue, Jiang Xinjian, Zhang Chaoping, et al.Optimization control strategies of large capacity flywheel energy storage system[J]. Transactions of China Electrotechnical Society, 2014, 29(3): 75-82. [15] Ghanaatian M, Lotfifard S.Control of flywheel energy storage systems in the presence of uncer- tainties[J]. IEEE Transactions on Sustainable Energy, 2019, 10(1): 36-45. [16] Chen Wenhua, Yang Jun, Guo Lei, et al.Disturbance- observer-based control and related methods-an over- view[J]. IEEE Transactions on Industrial Electronics, 2015, 63(2): 1083-1095. [17] 朱进权, 葛琼璇, 王晓新, 等. 基于自抗扰和负载功率前馈的高速磁悬浮系统PWM整流器控制策略[J]. 电工技术学报, 2021, 36(2): 320-329. Zhu Jinquan, Ge Qiongxuan, Wang Xiaoxin, et al.Control strategy for PWM rectifier of high-speed maglev based on active disturbance rejection control and load power feed-forward[J]. Transactions of China Electrotechnical Society, 2021, 36(2): 320-329. [18] Hu Yashan, Zhu Zhiqiang, Odavic M.Comparison of two-individual current control and vector space decomposition control for dual three-phase PMSM[J]. IEEE Transactions on Industry Applications, 2017, 53(5): 4483-4492. [19] 杨金波, 杨贵杰, 李铁才. 双三相永磁同步电机的建模与矢量控制[J]. 电机与控制学报, 2010, 14(6): 1-7. Yang Jinbo, Yang Guijie, Li Tiecai.Modeling and vector control for dual three-phase PMSM[J]. Electric Machines and Control, 2010, 14(6): 1-7. [20] 王鹿军, 张书烨, 赵思锋, 等. 基于NPC型三电平变换器的高速磁悬浮飞轮同步载波驱动技术[J/OL]. 电机与控制学报: 1-12[2023-01-06]. http://kns.cnki.net/kcms/detail/23.1408.TM.20220228.0907.002.html. Wang Lujun, Zhang Shuye, Zhao Sifeng, et al. Synchronous carrier drive technology of high speed magnetic suspension flywheel based on NPC three level converter[J/OL]. Electric Machines and Control: 1-12[2023-01-06]. http://kns.cnki.net/kcms/detail/23.1408.TM.20220228.0907.002.html. [21] 曹文远, 韩民晓, 谢文强, 等. 基于扰动观测器的电压源型逆变器负载电流前馈控制及参数设计方法[J]. 电工技术学报, 2020, 35(4): 862-873. Cao Wenyuan, Han Minxiao, Xie Wenqiang, et al.A disturbance-observer-based load current feedforward control and parameter design method for voltage- sourced inverter[J]. Transactions of China Electro- technical Society, 2020, 35(4): 862-873. [22] 章回炫, 范涛, 边元均, 等. 永磁同步电机高性能电流预测控制[J]. 电工技术学报, 2022, 37(17): 4335-4345. Zhang Huixuan, Fan Tao, Bian Yuanjun, et al.Predictive current control strategy of permanent magnet synchronous motors with high performance[J]. Transactions of China Electrotechnical Society, 2022, 37(17): 4335-4345. [23] 鲍旭聪, 王晓琳, 顾聪, 等. 超高速永磁电机驱动系统电流环稳定性分析与改进设计[J]. 电工技术学报, 2022, 37(10): 2469-2480. Bao Xucong, Wang Xiaolin, Gu Cong, et al.Stability analysis and improvement design of current loop of ultra-high-speed permanent magnet motor drive system[J]. Transactions of China Electrotechnical Society, 2022, 37(10): 2469-2480. [24] Briz F, Degner M W, Lorenz R D.Analysis and design of current regulators using complex vectors[J]. IEEE Transactions on Industry Applications, 2000, 36(3): 817-825. [25] 余晨辉, 汪凤翔, 林贵应. 基于在线扰动补偿的三电平PWM整流器级联式无差拍控制策略[J]. 电工技术学报, 2022, 37(4): 954-963. Yu Chenhui, Wang Fengxiang, Lin Guiying.Cas- caded deadbeat control strategy with online dis- turbance compensation for three-level PWM recti- fier[J]. Transactions of China Electrotechnical Society, 2022, 37(4): 954-963. [26] 吴为, 丁信忠, 严彩忠. 基于复矢量的电流环解耦控制方法研究[J]. 中国电机工程学报, 2017, 37(14): 4184-4191, 4298. Wu Wei, Ding Xinzhong, Yan Caizhong.Research on control method of current loop decoupling based on complex vector[J]. Proceedings of the CSEE, 2017, 37(14): 4184-4191, 4298.
2023, Vol. 38 
